mx23: Document the tRAS lockout setting in memory initialization

Add a comment about the tRAS lockout setting of HW_DRAM_CTL08 to
enable the 'Fast Auto Pre-Charge' found in the memory chip. The
setting is applied after memory initialization and it is worth
document it.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>

diff --git a/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c b/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
index 4a0a5aac7c01d5fe00c050a48174d4e502913808..fdac73cfaaf7476a3a08ebcb31a5891ceebfced4 100644 (file)
--- a/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
+++ b/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
@@ -120,6 +120,10 @@ static void initialize_dram_values(void)
                writel(dram_vals[i], MXS_DRAM_BASE + (4 * i));
 
 #ifdef CONFIG_MX23
+       /*
+        * Enable tRAS lockout in HW_DRAM_CTL08 ; it must be the last
+        * element to be set
+        */
        writel((1 << 24), MXS_DRAM_BASE + (4 * 8));
 #endif
 }